How severe is CVE-2024-21309?

CVE-2024-21309 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2024-21309 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-21309?

CVE-2024-21309 primarily affects Microsoft Windows 11 21h2. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-21309?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2024-21309 have an EU (EUVD) identifier?

Yes. CVE-2024-21309 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-19022.

When was CVE-2024-21309 published?

CVE-2024-21309 was published on 2024-01-09 and last updated on 2026-06-17.

CVE-2024-21309

CVE-2024-21309 is a high-severity vulnerability in Microsoft Windows 11 21h2 with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-191.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-19022
Weakness: CWE-191
Affected product: Microsoft Windows 11 21h2
Published: 2024-01-09
Last modified: 2026-06-17

Description

Windows Kernel-Mode Driver Elevation of Privilege Vulnerability

Frequently asked questions

What is CVE-2024-21309?: Windows Kernel-Mode Driver Elevation of Privilege Vulnerability
How severe is CVE-2024-21309?: CVE-2024-21309 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2024-21309 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-21309?: CVE-2024-21309 primarily affects Microsoft Windows 11 21h2. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-21309?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-21309 have an EU (EUVD) identifier?: Yes. CVE-2024-21309 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-19022.
When was CVE-2024-21309 published?: CVE-2024-21309 was published on 2024-01-09 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21309

Affected products (5)

cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:x64:*

More vulnerabilities in Microsoft Windows 11 21h2

CVE-2024-38199 — Critical (CVSS 9.8): Windows Line Printer Daemon (LPD) Service Remote Code Execution Vulnerability
CVE-2024-38140 — Critical (CVSS 9.8): Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution Vulnerability
CVE-2024-38063 — Critical (CVSS 9.8): Windows TCP/IP Remote Code Execution Vulnerability
CVE-2024-30080 — Critical (CVSS 9.8): Microsoft Message Queuing (MSMQ) Remote Code Execution Vulnerability
CVE-2023-36397 — Critical (CVSS 9.8): Windows Pragmatic General Multicast (PGM) Remote Code Execution Vulnerability
CVE-2023-36028 — Critical (CVSS 9.8): Microsoft Protected Extensible Authentication Protocol (PEAP) Remote Code Execution Vulnerability

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